1978129 has 8 divisors (see below), whose sum is σ = 2043360. Its totient is φ = 1913856.

The previous prime is 1978117. The next prime is 1978153. The reversal of 1978129 is 9218791.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1978129 - 2⁹ = 1977617 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1978159) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7569 + ... + 7825.

It is an arithmetic number, because the mean of its divisors is an integer number (255420).

2^1978129 is an apocalyptic number.

It is an amenable number.

1978129 is a deficient number, since it is larger than the sum of its proper divisors (65231).

1978129 is a wasteful number, since it uses less digits than its factorization.

1978129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 479.

The product of its digits is 9072, while the sum is 37.

The square root of 1978129 is about 1406.4597399144. The cubic root of 1978129 is about 125.5311584355.

The spelling of 1978129 in words is "one million, nine hundred seventy-eight thousand, one hundred twenty-nine".